Millennial is the name given to the generation born from 1981 to 1996, dates now clarified by the Pew Research Center, although some have seen them as starting in 1980 and being born as late as 2004. Also known as Generation Y (Gen Y), the millennial generation follows Generation X (Gen X). In terms of numbers, it has edged out the baby boomers as the most significant generation in American history.